Key off my battery reads 12.3v, key on it reads 11.8v - but no drop when pressing the starter button. All of the electrics are fully functional and upon pressing the starter button I can hear the solenoid click, but no action from the starter motor. Side stand is up and (for once) I can be confident that it is in neutral (clutch in makes no odds). Toggling the kill switch between the two off positions and the on position seems to show that contact is being made for the on position - so I don’t think that is the issue here. The battery was new in April this year. The bike was last run four days ago (on a 35mile relatively high speed round trip with the headlight on) - so I guess that should have been enough to keep the battery charged up? There is no corrosion evident on the electrical contacts that I can get to without pulling the fairing off.
Any ideas appreciated. I found on the web that the battery should actually read 12.6V (allegedly)- is the small difference compared to my readings really that significant?
I assume that the 750ss has got a starter fuse? If you haven’t checked it already…
Failing that, it can be worth connecting the positive of the battery to the positive on the starter (with a thick cable!) and checking that the starter operates. If it does
then I would start to suspect the starter relay - they can ‘click’ but still not conduct (ie. is could be knackered).
Try putting your meter onto the terminal on the starter motor , then pressing the starter button . If you get 11volts there the issue is with the starter motor. If no voltage then check the solenoid output . Could be a fuse as said , or the solenoid itself . Good luck.
12.3V is low to start with; your second reading indicates that with minimal load (probably only fuel pump) it drops below 12V - not good at all.
The first thing is to load-test the battery in isolation; this can be done with a load-tester (most garages will have one & will do it for free if you ask nicely), or to somehow hot-wire it to the starter motor to provide a load, for instance using jump leads, and read the voltage while cranking (1 or 2 seconds will do). My guess is that it will go through the floor. If that’s the case don’t waste your time: get a new battery (unless it’s very new, in which case the fault could lie elsewhere).
Once you’ve eliminated the battery from the equation you can start looking into more exciting things.
The problem is solved! I tried all the usual stuff (connecting live direct from battery to starter, live to output on solenoid, new solenoid, etc.) Sometimes the starter would turn when given a direct feed and other times it wouldn’t. Checked the earths, started to check voltages - 12.4 V into solenoid, 12.4 V out of solenoid, continuity from output to starter. Everything checked out OK. However, when double checking continuity from starter to solenoid output I got erratic readings - which I finally realised depended upon whether I was probing the nut or the pillar. Removed the nut, cleaned it up and reinstalled it - still no continuity! New nut & problem solved! Very odd.
Even the more odd, was the fact that the problematic nut was not ‘corroded’ in the usual sense and no corrosion was on the pillar - it simply had 20 odd years of (seemingly) non liquid driven oxidization (i.e. it just looked like a dull old nut).
One comment though: if there is no continuity where there should be, then there IS something wrong. But continuity alone is not an indication of a healthy circuit and it can even give misleading information; a battery cable with only one strand left will show perfect continuity and no resistance, but it will not carry enough current to turn a starter motor; only a voltage drop test will give you true information on the health of a circuit.
The connections from the solenoid to starter are known to be a problem. They are right in the line of fire for the c**p off the front wheel.
get heavier duty eye connectors and thicker wire. Will improve starting no end.
ive done it on all my ducatis, inc a 1994 750ss.
